var app1 = new Vue({
    el: '#app1',
    data :{
        info : '我是一个测试数据！',
        intervalId : null,
    },
    methods : {
        go() {
            if (this.intervalId != null) {
                return;
            }

            this.intervalId = setInterval(()=>{
                this.info = this.info.substring(1) + this.info.substring(0, 1);
            }, 500);
        },

        stop() {
            clearInterval(this.intervalId);
            this.intervalId = null;
            
            
        }
    }

})